This invention relates generally to vacuum cleaner with an agitator, such as a rotary brush, used for easy suction of dust.
In conventional vacuum cleaners having an agitator around the suction inlet, a detecting element or a sensor is provided to detect the rotating state of the agitator, which is usually a rotary brush, and an electrical motor driving the rotary brush is controlled using an output from the sensor. More specifically, the control of the motor is effected such that power supply to the motor is cutoff when the rotation of the motor is interrupted due to overload applied to the rotary brush. Therefore, a user can remove a cause of such overloaded state and restart the motor after a safety state is achieved again. However, in actual usage, when a user removes a substance applying overload to the rotary brush, the sensor has a chance to detect the slight rotation of the brush when an external force is applied by a user, and this may result in a dangerous state that the motor suddenly starts rotating.